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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        var arr = [10, 15, 2, 32, 5, 4, 20, 8, 48, 54, 6]
        // var idx = 0 //  创建新数组的索引
        var arr1 = [] //  创建个新数组
        for (var i = 0; i < arr.length; i++) {
            if (arr[i] < 10) { // 判断数组中小于10的数值
                arr1.push(arr[i])
                // arr1[idx] = arr[i] //  有的话赋值给新数组arr1
                // idx++ //  每次添加后索引+1
            }
        }
        console.log(arr1)
    </script>
</body>

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